Device for feeding powdered fuel.



"T 'dZZ ilk/tom it hwy concern:

iBeitknow'nthat I, JOHN L. BOARDMAN, a citizen of the'United States, residing at 1: Billings, in the county of Yellowstone and of Montana, have invented new and ,luseful Improvements in Devices for Feeding Powdered Fuel, of which the following is a specification.

1., This invention relates to means for utilizi'ngp owderedor pulverizedfuel for burning under boilers and furnaces, and pertains especially to a device for utilizing coal dust as a fuelon locomotives,

The principle of the invention depends upon the fact that a certain definite and predeterminable ambunt of oxygen is required for the proper combustion of carbonaceous fuels, and where powdered fuel such as coal dust is used, it-is highly essential that the right proportions. of air and fuel are maintained uniformly and continuously, irrespective of the joltings, drafts, and other condi tions incident to locomotive use and travel,

, which tend to disarrange and disturb such proportions.

In regard to the present invention it may be said generally that the fuel to. be used is first powdered or pulverized and dried, and

.. then stored in an inclosed tank or hopper on the tender of the engine, whence it is fed by 'a conveyer toa centrifugal fan; the fan mixing it with the proper amount of air for its completecombustion and blowing it into the fire box.

The invention resides in the combination and arrangement of the devices by which the l idea of the use of this powdered fuel under the conditions of locomotive use, is made ,commerclally ava lable.

The invention consists of the parts and the combination and construction of parts as hereinafter more fully described. and

claimed, having reference to the accompanyvention. Fig. 2is a vertical section on l1ne .2.2 of Fig-,1. Fig. 3. is asection through ing drawings, in which Figure 1 s a .plan v ew illustratlng the inthedust bin and conveyer. Fig. Al is a vertical section on line -l4 Fig. 1,- showing the arrangement of the fan and turbine.

j A is a binor hopper on. the tender having an "inclined bottom with a discharge slot2 through which the powdereddry dust may be fed by gravity upon an mcl ned conveyer belt 3. This conveyer belt 3 is of any ap- STATES PATENT OFFICE;

JOHN L. BQARDMAN, or ZBILLINGS, M0NT. AN\A.W 7

IDEVICE FOR Fnnnrne rownnrmn Even. I

Specification of Letters Patent. Pat'ented Feb. 29, 1916. a plicationfiled April 17, 1e15. Serial No. 22,087 j propriate construction, preferably of flexithe dust after mixture with the'proper quantity of air is blown through the discharge pipe 6. and nozzle 7 into the fire box'8. "In order to prevent slippage of the conveyer 3, the latter is provided with endless side chains 10 running over drive sprockets 11 at the head end of the belt, which sprockets are driven by the gear connections 12 from the steam turbine 13; this turbine 13 receiving its steam from the engine boiler.

The depth of the dust on the conveyer is adjusted by means 'ofa block 15 set in front of the opening in the hopper which is rig idly secured at'a predetermined height to allow a greater or less thickness of dust to pass on the belt. 16 represent a series of rollers underneath the belt and below the hopper opening 2 and are for the purpose of supporting the belt against the weight of the dust over the opening in the hopper, andfor supporting the belt at the proper, distance against the block 15 that strikes the measure of the fuel on the belt. ,These rollers 16 prevent the belt from sagging'and becoming-too full. The dust that is carried upward bylthe belt is dumped on to a sloping gable 18 which allows it to fall or slide over the edge of, the fan-housing and down to the intakeopenings 19 of the fan, where it is drawn into. and mixed with the air in the fan and then blown into the fire box. The casing 20 of the conveyer projects down to the upper edge of the intake openings, and, a pair of wings 21 are provided between the fan housing and this projection of the conveyer casing, which serve to guide the dust to the intake openings. Pan 22 is provided at the lower side of the intake .in such manner that it will not turbine is of sufiicient size to drive the fan and terminates 'in the flared metal mouthv thereby putting an equal amount of friction piece or nozzle 7, which admits the mixture of fuel and air along the front of the fire-box, without materially changing the area at anyplace soas to make an excessive velocity at entrance into the fire-box.

The fire-box. may be of the same type and in fact the same fire-box asis used at present, with the usual fire brick arch 24:, but the grates must be practically'air tight when closed, and be'of the design that maybe tipped and emptied through any suitable connections 25, by means of a lever, not shown, in the engine cab. The ash pans are also made air tight when closed, and may be opened from the cab by any well known means, not necessary here to be shown. The fire-box and ash pan are so arranged that but one of them need be opened at the same time, thus preventing the escape of the burning fuel and preventing a sudden rush of cold air into the fire-box.

Among the advantages gained by the use of this device may be mentioned the following: The fine coal which is now an expense to the coal mining operators may be used with the same ratio of efficiency as the best lump coal; all of the fuel value or heat energy is taken out of the coal and passed through the boiler tubes in the form of heat;

the temperature of the fire-box is controlled at will, and may be kept constant, thus saving the wear and tear due to sudden rushes of cold air when the fire door is opened; fuel saving does not depend upon the. judgment of the fireman, but is done automatically and mechanically.

The special features of the invention 1tself are these: First and foremost, it is adapted to locomotive use.

fuel is taken from the levelof the floor of the tender or from below this level if required, to the top of the fan. This is a very necessary item on account of the restricted amount of room available both in vertical and horizontal distancef Powdered fuelis conveyed to the top of the fan and d1stributed' equally to both intake openings,

on each intake opening of the fan, and -insuring an e ual amount of mixtureof fuel and air. e conveyer belt 'is positively driven at a uniform rate of speed with re spect to .the fan, so that there is absolutely .assurred a maintenance of the. proper proportion of fuel and. airat. all times no mat- "ter. how rough and variable. the Working The powdered more, by direct gearing of the fan and belt driving means to the turbine a constant speed may be maintained further conducing to efficiency.

Having thus described my invention, what I claim and desire to secure by Letters Patent is 1. A device for feeding powdered fuel consisting in the combination of a bin havfan toreceive the mixture of air and fuel,

said conveyer delivering the material to the topof the fan and discharging it into the intakes on opposite sides of the fan, simultaneously with'the air that is drawn into the fan from both sides thereof.

2. A device for feeding powdered fuel.

consisting of a bin having a sloped bottom with a discharge outlet therein, an inclined conveyer beneath the out-let, a spacing bar in conjunction with the outlet and adapted to regulate the depthof fuel on the conveyer, a centrifugal fan onto the top of which said conveyer is adapted to deliver the material, said fan having opposite side air inlets, and means for directing the material discharged from the conveyer into the inlets in the fan whereby the air and fuel is drawn into the fan from both sides of the latter, and a burner nozzle from the fan to receive the mixture of air and fuel.

3'. A device for feeding powdered fuel to a furnace including a fan having a discharge leading to the furnace. and having oppositely disposed side inlets, a source of powdered fuel supply, means to convey the fuel to the fan and simultaneously into. said opposite side inlets thereof and meanswhereby to enable air to be drawn in with the fuel from both sides'of the fan.

4. A'device for feeding powdered fuel to a furnace including a fan having a housing the top of which is gabled, said housing havi oppositeside inlets, a casing spaced from and 'inclosing the fan housing and .havin side air inlets, means to convey the fuel on top of the gabled housing, means to direct the fuel towardthe housing inlets, and means to convey the fuel and air to the furnace.

5. A device. for feeding powdered fuel to.

a furnace, including a housing-the top of which is gabled, said housing having a pair of opposite inlets in its sides, a shaft l1av inga fan thereon which shaft extends cen-.

trally through said inlets, a casing extending over the gable and sides of said housing in spaced relation'to said gable and housing sides and having side air inlets which latter register with the respective inlets of the sides which air inlets register with the fan inlets, means in the space between the housing and casing sides to direct fuel to each of the fan housing inlets. and means to feed fuel to the fan housing.

In testimony whereof I have hereunto set my hand in the presence of twq subscribing witnesses.

JOHN L. BOARDHAN.

'itnesses JAMES J. CARRIGAN, M. EJCALLAIIAN. 

